Mechanisms for forming image sensor device

Abstract

Embodiments of mechanisms for forming an image sensor device are provided. The image sensor device includes a semiconductor substrate and a photodetector in the semiconductor substrate. The image sensor device also includes a dielectric layer over the semiconductor substrate, and the dielectric layer has a recess aligned with the photodetector. The image sensor device further includes a filter in the recess of the dielectric layer. In addition, the image sensor device includes a shielding layer between the dielectric layer and the semiconductor substrate and surrounding the filter.

What is claimed is: 
     
       1. An image sensor device, comprising:
 a semiconductor substrate; 
 a photodetector in the semiconductor substrate; 
 a dielectric layer over the semiconductor substrate, wherein the dielectric layer has a recess aligned with the photodetector; 
 a filter in the recess of the dielectric layer, wherein the filter has a protruding portion protruding from a bottom surface of the dielectric layer; 
 a shielding layer between the dielectric layer and the semiconductor substrate and surrounding the filter, wherein the filter and the shielding layer overlap from a view facing a direction perpendicular to a normal direction of a top surface of the semiconductor substrate, and the shielding layer surrounds the protruding portion of the filter; and 
 a reflective element directly below the shielding layer, wherein the shielding layer is thinner than the reflective element. 
 
     
     
       2. The image sensor device as claimed in  claim 1 , wherein a bottom of the shielding layer is substantially coplanar with a bottom of the filter. 
     
     
       3. The image sensor device as claimed in  claim 1 , wherein the shielding layer comprises a metal material. 
     
     
       4. The image sensor device as claimed in  claim 1 , further comprising a lens over the photodetector. 
     
     
       5. The image sensor device as claimed in  claim 1 , further comprising an anti-reflection layer between the semiconductor substrate and the shielding layer. 
     
     
       6. The image sensor device as claimed in  claim 1 , further comprising:
 a second dielectric layer surrounding the reflective element, wherein the second dielectric layer is between the semiconductor substrate and the dielectric layer. 
 
     
     
       7. The image sensor device as claimed in  claim 6 , wherein materials of the reflective element and the shielding layer are the same. 
     
     
       8. The image sensor device as claimed in  claim 6 , further comprising:
 a black level correction region in the semiconductor substrate; and 
 a shielding element over the black level correction region, wherein materials of the shielding element and the reflective element are the same. 
 
     
     
       9. An image sensor device, comprising:
 a semiconductor substrate having a first pixel region and a second pixel region; 
 a first photodetector and a second photodetector in the first pixel region and the second pixel region, respectively; 
 a dielectric layer over the semiconductor substrate, wherein the dielectric layer has a first recess and a second recess aligned with the first photodetector and the second photodetector, respectively; 
 a first filter and a second filter in the first recess and the second recess, respectively, wherein the first filter has a protruding portion protruding from a bottom surface of the dielectric layer; 
 a shielding layer between the dielectric layer and the semiconductor substrate and surrounding the first filter and the second filter, wherein the first filter and the shielding layer overlap from a view facing a direction perpendicular to a normal direction of a top surface of the semiconductor substrate, and the shielding layer surrounds the protruding portion of the first filter; and 
 a reflective element directly below the shielding layer, wherein the shielding layer is thinner than the reflective element. 
 
     
     
       10. The image sensor device as claimed in  claim 9 , wherein the second filter has a second protruding portion protruding from a bottom surface of the dielectric layer, and the shielding layer surrounds the second protruding portion of the second filter. 
     
     
       11. The image sensor device as claimed in  claim 9 , wherein a bottom of the shielding layer is substantially coplanar with bottoms of the first filter and the second filter. 
     
     
       12. The image sensor device as claimed in  claim 9 , wherein the shielding layer comprises a metal material, a polymer material, a semiconductor material, a ceramic material, or a combination thereof. 
     
     
       13. The image sensor device as claimed in  claim 9 , wherein a thickness of the shielding layer is in a range from about 10 nm to about 500 nm. 
     
     
       14. An image sensor device, comprising:
 a semiconductor substrate; 
 a photodetector in the semiconductor substrate; 
 a filter over the semiconductor substrate and aligned with the photodetector; 
 a dielectric layer over the semiconductor substrate and surrounding the filter; 
 a shielding layer over the semiconductor substrate and surrounding a lower portion of the filter, wherein the lower portion of the filter protrudes from a bottom surface of the dielectric layer, and the shielding layer and the lower portion of the filter overlap from a view facing a direction perpendicular to a normal direction of a top surface of the semiconductor substrate; and 
 a reflective element directly below the shielding layer, wherein the shielding layer is thinner than the reflective element. 
 
     
     
       15. The image sensor device as claimed in  claim 14 , wherein bottoms of the shielding layer and the filter are substantially coplanar with each other. 
     
     
       16. The image sensor device as claimed in  claim 14 , wherein the shielding layer comprises a metal material. 
     
     
       17. The image sensor device as claimed in  claim 14 , further comprising:
 a second dielectric layer surrounding the reflective element, wherein the second dielectric layer is between the semiconductor substrate and the filter. 
 
     
     
       18. The image sensor device as claimed in  claim 17 , wherein materials of the shielding layer and the reflective element are substantially the same. 
     
     
       19. The image device as claimed in  claim 1 , wherein the reflective element is separated from the shielding layer. 
     
     
       20. The image device as claimed in  claim 1 , wherein the shielding layer is wider than the reflective element.